A 911 caller reported seeing a person with a gun at Fallbrook High School on Tuesday afternoon, prompting an hour-long lockdown at the school, but no gunman was found, a San Diego County sheriff's lieutenant said.

At 1:35 p.m. the caller who reported the gunman, said "Hurry," and then hung up the phone, Lt. Julie Sutton said.

Deputies contacted the school, which ordered students locked in their classrooms as deputies did a room-to-room search. After an hour of searching, they came up empty.

"It was determined that it was safe to cancel the lockdown (about 3 p.m.) and students were released," Sutton said.